This invention relates to an improved control system for an intraocular surgical instrument that can be used with microsurgical scissors, forceps, knives and the like. More particularly, this embodiment of the invention relates to an apparatus for detecting intraocular surgical scissors. More particularly, this embodiment of the invention relates to an apparatus for detecting and distinguishing between different types of intraocular surgical scissors.
The invention will be described in connection with its preferred use as a portion of the control system for intraocular surgical scissors. The use of intraocular surgical scissors is well known. While manually operated scissors are still in widespread use worldwide, the use of surgical scissors with electric motor drive is also widespread. Electrical motor driven scissors are divided into two well known types based upon the type of drive, those that are solenoid actuated and those that are driven by a direct current motor or proportional control.
Most intraocular scissors have design similarities in which a pair of cutting blades extend from the end of a tubular needle with one blade being fixed and the opposite opposing blade end being reciprocated between an open and a closed position with respect to the fixed blade. This reciprocating motion is accomplished through the action of one of the driving systems such as, for example, the manual or electric motor drive.
Electric motor drivers of either rotary or linear solenoid type activate scissor closure by controlled transfer of the motor energy to the movable blade. The scissors may be of the vertical design, the guillotine or parallel blade type, the angled or horizontal-style or of other design or the scissors may be replaced by other instruments that operate similarly. The linear solenoid type provides a reciprocating action in which the electrical actuation of a solenoid causes the movable blade to move to the closed position in relation to the fixed blade and then, usually through the operation of a spring, to return to the open position. The rotary electric motor drive may also be considered as a "proportional-cut" mode of operation as the motor is typically a stepper or rotary motor. The motion of the movable blade is controlled by the surgeon and the rate and amount of closure of the blade is proportional to the rate and amount of movement of the control by the surgeon.
It may be easily seen that the operation of the Different electrical motor drives requires different controls and that connection of the wrong control system could cause problems.